Unidentified particles spotted in Saturn's atmosphere by Cassini

Cassini sent data about Saturn's atmosphere, which shows that more than just water particles are present there

NASA's Cassini spacecraft continues to display amazing and surprising discoveries, although it burnt up about a month ago when it took its mission-ending dive into Saturn. Now, new data have emerged from the probe, which suggests that Saturn's majestic rings are showering tiny dust particles into the planet's upper atmosphere and they are also forming a complicated and unexpected chemical mix in there.

While the space probe was travelling between Saturn and its rings during the final five months prior to its end, a mass spectrometer aboard Cassini detected this strange chemistry, suggests a recent report.

"We really hit the jackpot," said Mark Perry, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. Perry reported these findings on October 17 at a meeting of the American Astronomical Society's Division for Planetary Sciences in Provo, Utah.

As per a report by Nature.com, mission scientists had expected Cassini's mass spectrometer to spot the signature of water molecules, as the spacecraft looped between the planet and its rings. NASA's Pioneer and Voyager missions during the 1970s and 80s had found fewer charged particles than expected in Saturn's uppermost atmosphere. Based on the data, researchers in 1984 had proposed that water molecules that come off the rings, mostly in the ice form, act as catalysts to strip charged particles from the atmosphere. This latest data from Cassini's final months of investigation gave scientists the first opportunity to actually examine this idea directly.

The mass spectrometer revealed data about a host of chemicals, including methane, a molecule that could be carbon monoxide and many more-complex molecules. The layers of these chemicals are the thickest at around the equator of the planet and at high altitudes, which hints towards the fact that those materials are, indeed, shedding off Saturn's rings.

As per the report, the deeper Cassini dug in, the stranger its measurements became. The probe's closest swings by Saturn's surface unveiled an impressive collection of heavy molecules, said Perry at the conference. Although all the molecules have not yet been identified and pinpointed by the scientists, clearly it's certain that there is much more than just water around.

By analysing and predicting the types of material that could come off the rings, Perry's team accomplished that the remains must be fragments of tiny dust particles that measure just about 1 to 10 nanometres across, however; they are relatively heavy. As per the information gathered, these particles shattered into small pieces as soon as they spiralled off the rings and slammed into Cassini's mass spectrometer.

"We have a lot of work to do to understand how they are getting in there. None of the models predict this," said Perry.